Injectors normally comprise a hollow body fitted with an injection nozzle and a fuel metering valve; and a support fitted to the hollow body and housing an electromagnet controlling the valve. More specifically, the support comprises a sleeve inserted in fluidtight manner inside a cylindrical cavity in the hollow body; and an end wall having a discharge conduit and on which an edge of the sleeve is bent to lock the electromagnet.
In known technology, the sleeve is fitted to the hollow body by means of a threaded ring nut screwed to an external thread on the hollow body. Such a system has various drawbacks. In particular, the hollow body must have a cylindrical portion on which to form the thread, so that the ring nut is larger in diameter than the threaded portion, and the injector therefore relatively wide. Moreover, the thread and ring nut call for additional machining, which makes the injector fairly expensive to produce; and the two threads may retain machining debris or other solid particles which, when assembling the injector, get into the conduits, thus impairing operation of the injector.